Abstract:
Drought, bringing the risks of agricultural production losses, is becoming a globally environmental stress. Previous results suggested that legumes with nodules exhibited superior drought tolerance compared with the non-nodule group. To investigate the molecular mechanism of rhizobium symbiosis impacting drought tolerance, transcriptome and sRNAome sequencing were performed to identify the potential mRNA-miRNA-ncRNA dynamic network. Our results revealed that seedlings with active nodules exhibited enhanced drought tolerance by reserving energy, synthesizing N-glycans, and medicating systemic acquired resistance due to the early effects of symbiotic nitrogen fixation (SNF) triggered in contrast to the drought susceptible with inactive nodules. The improved drought tolerance might be involved in the decreased expression levels of miRNA such as mtr_miR169l-5p, mtr_miR398b, and mtr_miR398c and its target genes in seedlings with active nodules. Based on the negative expression pattern between miRNA and its target genes, we constructed an mRNA-miR169l-ncRNA ceRNA network. During severe drought stress, the lncRNA alternative splicings TCONS_00049507 and TCONS_00049510 competitively interacted with mtr_miR169l-5p, which upregulated the expression of NUCLEAR FACTOR-Y (NF-Y) transcription factor subfamily NF-YA genes MtNF-YA2 and MtNF-YA3 to regulate their downstream drought-response genes. Our results emphasized the importance of SNF plants affecting drought tolerance. In conclusion, our work provides insight into ceRNA involvement in rhizobium symbiosis contributing to drought tolerance and provides molecular evidence for future study.
摘要:
干旱,带来农业生产损失的风险,正在成为全球环境压力。先前的结果表明,与无结节组相比,有结节的豆科植物表现出更好的耐旱性。探讨根瘤菌共生影响耐旱性的分子机制,进行转录组和sRNAome测序以鉴定潜在的mRNA-miRNA-ncRNA动态网络。我们的结果表明,具有活性根瘤的幼苗通过储存能量表现出增强的耐旱性,合成N-聚糖,和由于共生固氮(SNF)的早期作用而引起的系统性获得性抗性,这与干旱易感的不活跃结节相反。耐旱性的提高可能与mtr_miR169l-5p等miRNA表达水平的降低有关。mtr_miR398b,和具有活性根瘤的幼苗中的mtr_miR398c及其靶基因。基于miRNA与其靶基因之间的阴性表达模式,我们构建了一个mRNA-miR169l-ncRNAceRNA网络。在严重干旱胁迫期间,lncRNA选择性剪接TCONS_00049507和TCONS_00049510与mtr_miR169l-5p竞争性相互作用,上调NF-Y(NF-Y)转录因子亚家族NF-YA基因MtNF-YA2和MtNF-YA3的表达,以调节其下游干旱反应基因。我们的结果强调了SNF植物影响耐旱性的重要性。总之,我们的工作提供了对CERNA参与根瘤菌共生有助于耐旱性的见解,并为未来的研究提供了分子证据。